Leveraging multiprocessor fabric link aggregation

ABSTRACT

Data access patterns between at least three nodes within a single symmetric multiprocessing server may be monitored by at least one hypervisor. At the hypervisor, mappings for the data access patterns may be generated for the at least three nodes. Based upon the mappings, the hypervisor may determine that the data access patterns for at least two of the at least three nodes are outside of a bandwidth threshold. In response to determining that the data access patterns for at least two of the at least three nodes are outside of a bandwidth threshold, the hypervisor may formulate an asymmetric cabling plan. Based upon the asymmetric cabling plan, a recommendation to alter the multiprocessor fabric link aggregation may be displayed to a user through a graphical user interface.

BACKGROUND

The present disclosure relates generally to multiprocessing, and moreparticularly, to fabric link aggregation within a multiprocessingserver. Multiprocessing allows a server to have multiple applicationsrunning simultaneously while sharing a common memory and balancingworkload requirements. As the number of applications and the varioususes of the applications increase, the need to balance the workloadrequirements within the multiprocessing server may also increase.

SUMMARY

Aspects of the disclosure provide a method, system, and computer programproduct for leveraging multiprocessor fabric link aggregation. Themethod, system, and computer program product may include monitoring, byat least one hypervisor, data access patterns between at least threenodes within a single symmetric multiprocessing server. At thehypervisor, mappings for the data access patterns may be generated forthe at least three nodes. Based upon the mappings, the hypervisor maydetermine that the data access patterns for at least two of the at leastthree nodes are outside of a bandwidth threshold. In response todetermining that the data access patterns for at least two of the atleast three nodes are outside of a bandwidth threshold, the hypervisormay formulate an asymmetric cabling plan. Based upon the asymmetriccabling plan, a recommendation to alter the multiprocessor fabric linkaggregation may be displayed to a user through a graphical userinterface.

The above summary is not intended to describe each illustratedembodiment or every implementation of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings included in the present application are incorporated into,and form part of, the specification. They illustrate embodiments of thepresent disclosure and, along with the description, serve to explain theprinciples of the disclosure. The drawings are only illustrative ofcertain embodiments and do not limit the disclosure.

FIG. 1 depicts one embodiment of an example computer processing systemwith a mappings generator and a cable planner.

FIG. 2 depicts one embodiment of an example symmetric multiprocessingserver having a symmetric cabling structure.

FIG. 3 depicts one embodiment of an example symmetric multiprocessingserver having an asymmetric cabling structure.

FIG. 4 depicts one embodiment of an example process for leveragingmultiprocessing fabric link aggregation.

While the embodiments described herein are amenable to variousmodifications and alternative forms, specifics thereof have been shownby way of example in the drawings and will be described in detail. Itshould be understood, however, that the particular embodiments describedare not to be taken in a limiting sense. On the contrary, the intentionis to cover all modifications, equivalents, and alternatives fallingwithin the spirit and scope of the invention.

DETAILED DESCRIPTION

Aspects of the present disclosure relate to multiprocessing servers, andmore particular aspects relate to leveraging fabric link aggregationwithin multiprocessing servers. Symmetric multiprocessing (SMP) involvesa symmetric multiprocessor system hardware and software architecturewhere two or more processors are connected to a single, shared memory,have full access to all input/output (I/O) devices, and are controlledby a single operating system that treats all processors equally. SMPsystems are tightly coupled multiprocessor systems with a pool ofprocessors running independently. Each processor may execute differentprograms and may work on different data while having the capability ofsharing common resources (e.g., memory, I/O devices) and connectingusing a system bus or a crossbar. SMP systems allow any processor towork on any task no matter where the data for that task is located inmemory, provided that each task in the system is not in execution on twoor more processors at the same time. In the case of multi-coreprocessors, the SMP architecture applies to the cores, treating them asseparate processors.

In contrast, in an asymmetric multiprocessing (AMP) system, not allprocessors are treated equally. For example, an AMP system may allow(either at the hardware or operating system level) one processor to onlyexecute operating system code or another processor to only perform I/Ooperations. In another example, an AMP system may allow any processor toexecute operating system code and perform I/O operations such that allprocessors are symmetric with respect to processor roles, but theprocessors may have additional peripherals (e.g., input, output, andsecondary storage devices) assigned to particular processors, so thatthey are asymmetric with respect to peripheral assignments.

SMP and AMP systems both utilize network topology for communicationbetween nodes and/or processors. Network topology is the arrangement ofvarious elements (e.g., links, nodes) of a computer network.Specifically, physical topology is the placement of the variouscomponents of a system, including device location and cableinstallation. In multi-node servers, cables between the nodes carry theinter-node traffic. Additionally, processors may be interconnected usingbuses, crossbar switches, or on-chip mesh networks. In conventionalsymmetric multiprocessing servers, the cables are symmetricallyconnected between the nodes such that each node is connected to everyother node with the same number of connections (e.g., a SMP systemconfiguration), thereby avoiding any latency in data access between anytwo nodes. For example, in a SMP system with four nodes, the first nodemay be connected to the second node with two cables, to the third nodewith two cables, and to the fourth node with two cables.

However, embodiments of the present disclosure provide a system andmethod for recommending an intentionally asymmetric cabling structurewithin a single symmetric multiprocessing server based on workloadrequirements. A hypervisor may monitor data access patterns between atleast three nodes within the single symmetric multiprocessing server. Bymonitoring the nodes, the hypervisor may create mappings (e.g., datatransformation) for the data access patterns. In some embodiments, dataaccess patterns may include the manner in which workloads running on onenode are accessing the resources (e.g., memory, accelerators) on othernodes. For example, in the case of memory read/writes, the frequency ofaccess and the size of writes may be used to determine a data accesspattern. In certain embodiments, the mappings may include the amount ofdata transferred between workloads across nodes, the amount of datatransferred to/from workloads from/to I/O adapters, or the amount ofdata transferred between the nodes by workloads operating in another oneof the nodes. When any of the data access patterns are outside of apredetermined bandwidth threshold, the hypervisor may devise anasymmetric cabling plan to alter the bandwidth in order to increase thebandwidth where the threshold was breached.

Hence, the embodiments described herein alleviate potential bottlenecksin the scalability of SMP systems using cables, buses, or crossbarswitches due to an uneven distribution of resources. That is, thebandwidth and power consumption of the connections among the variousprocessors, the memory, and the disk arrays may result in an unevendistribution of resources. For example, when multiple partitions arecreated to host multiple workloads on a multi-node server, it may beunnecessary for data access patterns and hence the bandwidth requirementbetween all nodes, to be symmetrical. By intentionally implementing anasymmetric cabling structure for a single SMP server, the embodimentsdescribed herein help alleviate such bottlenecks. While the presentdisclosure is not necessarily limited to such applications, variousaspects of the disclosure may be appreciated through a discussion ofvarious examples using this context.

Referring now to FIG. 1, a computer processing system 100 with amappings generator and a cable planner can be seen according to someembodiments. In some embodiments, the computer processing system 100 caninclude a processor 102, memory 114, and I/O (input/output) devices 122.

The processor 102 can execute instructions stored in memory 114 andperform various functions in the computer processing system 100. Theprocessor 102 can include, but is not limited to, a CPU core 104, aregister 106, a cache 108, and a mappings generator 110 which caninclude a cable planner 112. The CPU core 104 can provide logic for theprocessor 102. In some embodiments, the processor 102 can containmultiple CPU cores. The cache 108 and register 106 can provide storagefor data that is frequently accessed by the processor 102. In someembodiments, the computer processing system 100 can contain multipleprocessors 102 typical of a relatively large system. In someembodiments, the computer processing system 100 can be a singleprocessor system (e.g., an SMP/AMP system). The processor 102 caninclude various types of processors such as, digital signal processor(DSP) hardware, network processor, application specific integratedcircuit (ASIC), field programmable gate array (FPGA), or other types ofprocessors. The memory 114 can be coupled to the processor 102 via amemory bus 118.

The mappings generator 110 can monitor the data access patterns by theprocessor 102 to create real time mappings of the computer processingsystem 100. The cable planner 112 can be coupled to, or a part/subsystemof the mappings generator 110. According to some embodiments, the cableplanner 112 may provide a recommendation to alter the multiprocessorfabric link aggregation (hereinafter used interchangeably with the termcabling structure) of the computer processing system 100 based on themappings created at the mappings generator 110. In embodiments, themultiprocessor fabric link aggregation may be the physical topology of amulti-node server, such as connecting nodes with SMP cables.

The processor 102, the mappings generator 110, and the cable planner 112can be configured to operate as described in some embodiments. Forexample, the cable planner 112 can be configured to analyze the currentcabling structure of the computer processing system 100, devise analternative asymmetric cabling plan based upon mappings created at themappings generator 110, and recommend to a user which cables need to bemodified (e.g., change cable connection originating and terminatingports) to create an asymmetric cabling structure. The processor 102 orother logic device can be configured to monitor specific data accesspatterns between nodes of the computer processing system 100, such asthe amount of data transferred between workloads across nodes. In someembodiments, the mappings generator may utilize the data access patternsmonitored by the processor 102 to create mappings to be used by thecable planner 112.

The memory 114 can include a random-access semiconductor memory, storagedevice, or storage medium (either volatile or non-volatile) for storingor encoding data and programs. The memory 114 can be conceptually asingle monolithic entity, but in some embodiments, the memory 114 can bea more complex arrangement, such as a hierarchy of caches and othermemory devices. The memory 114 can store data (e.g., data 117),instructions, modules, and other types of information, hereaftercollectively referred to as “memory elements.” Although the memoryelements are illustrated as being contained within the memory 114, insome embodiments some or all of them can be on different devices and canbe accessed remotely, e.g., via a network.

The computer system 100 can use virtual addressing mechanisms that allowthe programs of the computer system 100 to behave as if they only haveaccess to a large, single storage entity instead of access to multiple,smaller storage entities. Thus, while the memory elements areillustrated as being contained within the memory 114, these elements arenot necessarily completely contained in the same storage device at thesame time. Further, although the memory elements are illustrated asbeing separate entities, in some embodiments some of them, portions ofsome of them, or all of them can be packaged together.

In some embodiments, the memory elements can include a softwareapplication 116 and data 117. The memory elements can be instructions orstatements that execute in the processor 102 to carry out someembodiments. The software application 116 can instruct the computerprocessing system 100 to carry out events or processes which aremonitored by the processor 102 using mappings generator 110 and thecable planner 112. The data 117 can be various types of data stored inmemory 114. In some embodiments, the data 117 can include data accesspatterns and/or mappings collected from the mappings generator 110 andasymmetric multiprocessor fabric link aggregations created at the cableplanner.

The processor 102 can also communicate with one or more I/O devices 122via an I/O bus 120. The I/O devices 122 can include, but are not limitedto, devices such as a keyboard, a pointing device, a display, one ormore devices that enable a user to interact with the computer processingsystem 100, and various devices (e.g., network interface card, modem,etc.) that enable the computer processing system 100 to communicate withone or more other computing devices. It should be understood that othersuitable hardware and software components can be used in conjunctionwith the computer processing system 100.

FIG. 2 depicts one embodiment of an example symmetric multiprocessingserver having a symmetric cabling structure. The SMP server 200 includesa plurality of nodes 202A-202D. In some embodiments, the nodes 202A-202Dcan include, but are not limited to, a plurality of respectiveprocessors P1A-P4A-P1D-P4D. In various embodiments, the processorsP1A-P4A-P1D-P4D may reside across multiple daughter cards. In certainembodiments, the plurality of processors P1A-P4A-P1D-P4D may include,but are not limited to, a plurality of originating ports for respectivecables 204A-204D. For example, as shown in the SMP server 200, eachprocessor P1A-P4A-P1D-P4D within each respective node 202A-202D hasthree respective cables (e.g., 204A-204D) connecting the processorsP1A-P4A-P1D-P4D to respective terminals T1A-T6A-T1D-T6D originating froma single point at each respective processor. In various embodiments, thethree cables connecting the processors P1A-P4A-P1D-P4D to terminalsT1A-T6A-T1D-T6D may each have a separate originating point within eachprocessor. The cables 204A-204D may be utilized as internode busconnections. In some embodiments, the cables 204A-204D may use paralleland/or bit serial connections to communicate data between the nodes202A-202D.

In the SMP server 200, each node 202A-202D has a plurality of respectiveterminals T1A-T6A-T1D-T6D. The terminals T1A-T6A-T1D-T6D connect thenodes 202A-202D through a plurality of cables 206. In variousembodiments, the terminals T1A-T6A-T1D-T6D may include indicator lightsfor cable identification. The plurality of cables 206 carry theinter-node traffic between the nodes 202A-202D. The plurality of cables206 in the SMP server 200 are arranged such that each node 202A-202D isconnected to every other node with the same number of connections. Forexample, at node 202A, the terminals T1A and T4A are connected to theterminals T1B and T4B of node 202B, the terminals T2A and T5A areconnected to the terminals T2C and T5C of node 202C, and the terminalsT3A and T6A are connected to the terminals T3D and T6D of node 202D.Similarly, at node 202C, the terminals T1C and T4C are connected to theterminals T2B and T5B of node 202B, the terminals T2C and T5C areconnected to the terminals T2A and T5A of node 202A, and the terminalsT3C and T6C are connected to the terminals T2D and T5D of the node 202D.Thus, each node within the SMP server 200 is connected to all othernodes through at least two terminals to reduce latency in data accessbetween the nodes 202A-202D.

FIG. 3 depicts one embodiment of an example SMP server having anasymmetric cabling structure. The SMP server 300 includes a plurality ofnodes 302A-302D. In some embodiments, the nodes 302A-302D can include,but are not limited to, a plurality of respective processorsP1A-P4A-P1D-P4D. In certain embodiments, the plurality of processorsP1A-P4A-P1D-P4D may include, but are not limited to, a plurality oforiginating ports for cables 304A-304D. For example, as shown in the SMPserver 300, each processor P1A-P4A-P1D-P4D within each node 302A-302Dhas three cables (e.g., 304A-304D) connecting the processorsP1A-P4A-P1D-P4D to respective terminals T1A-T6A-T1D-T6D originating froma single point at each respective processor. In various embodiments, thethree cables connecting the processors P1A-P4A-P1D-P4D to respectiveterminals T1A-T6A-T1D-T6D may each have a separate originating pointwithin each processor. The cables 304A-304D may be utilized as internodebus connections. In some embodiments, the cables 304A-304D may useparallel and/or bit serial connections to communicate data between thenodes 302A-302D.

In the SMP server 300, each node 302A-302D has a plurality of respectiveterminals T1A-T6A-T1D-T6D. The terminals T1A-T6A-T1D-T6D connect thenodes 302A-302D through a plurality of cables 306. In variousembodiments, the terminals T1A-T6A-T1D-T6D may include indicator lightsfor cable identification. The plurality of cables 306 carry theinter-node traffic between the nodes 302A-302D. In the example shown inFIG. 3, the SMP server 300 utilizes a recommended asymmetrical cablingplan generated in response to determining that the data access patternsbetween the nodes 302A-302D of the SMP server 300 have exceeded abandwidth threshold. For example, a hypervisor may determine that thedata access patterns between nodes in an SMP server (e.g., FIG. 2) areimbalanced such that a bandwidth threshold between two sets of nodes(e.g., 202A-202B and 202C-202D) has been exceeded. Thus, the SMP server300 may be arranged by changing the plurality of cables 306 to maximizebandwidth between nodes 302A-302B and nodes 302C-302D without losing asymmetric multiprocessor structure.

For instance, each node 302A-302D has at least one connection with everyother node in the SMP server 300 in order to ensure a multiprocessingconfiguration. Node 302A is connected to node 302B using terminal T6A toterminal T1B, to node 302C using terminal T5A to terminal T1C, and tonode 302D using terminal T2A to terminal T6D. Additionally, the SMPserver 300 has increased the bandwidth between the nodes 302A-302B and302C-302D because each set of two nodes shares four connection points.For example, nodes 302A and 302B are connected using the terminalsT1A-T6B, T3A-T4B, T4A-T3B, and T6A-T1B. Likewise, nodes 302C and 302Dare connected using the terminals T3C-T4D, T4C-T3D, T5C-T2D, andT6C-TD1. In some embodiments, the asymmetric configuration of the SMPserver 300 helps distribute resources between the nodes where requiredwithout encountering performance degradation.

FIG. 4 depicts one embodiment of an example process for leveragingmultiprocessing fabric link aggregation. The method 400 can beimplemented by a computing device, such as the processor 102implementing the mappings generator 110 and the cable planner 112. Invarious embodiments, a hypervisor may perform the same functions as themappings generator 110 and the cable planner 112. In certainembodiments, the SMP server may initially operate under a cabling planwhere the bandwidth between all the nodes within the SMP server areequal. At block 402, a hypervisor monitors data access patterns betweennodes within a SMP server. Data access patterns may include, but are notlimited to, the way in which workloads (e.g., the amount of workperformed by a node in a given period of time, or the average amount ofwork handled by a node at a particular instant of time) running on afirst node are accessing the resources on a second node. In anotherexample, the data access patterns may include access between processorslocated within the nodes and secondary caches, such as an off-processorcache, solid state drive (SSD), or long term storage device. In someembodiments, nodes within the SMP system may be monitored by a singlehypervisor which spans across the nodes of the SMP server. In otherembodiments, nodes within the SMP server may be monitored by a pluralityof hypervisors. For example, in a SMP server containing four nodes,three nodes may be run and monitored by one hypervisor (e.g., PowerVM®,PowerVM is a registered trademark of International Business MachinesCorporation of Armonk, N.Y.) and one node may be run and monitored by asecond hypervisor (e.g., PowerKVM™).

At block 404, the one or more hypervisors monitoring the data accesspatterns between the nodes of the SMP server generate mappings based onthe data access patterns. In some embodiments, generating mappings mayinclude data transformation and/or identification of data relationshipsas part of a data analysis. The mappings may include, but are notlimited to, the amount of data transferred between workloads acrossnodes, the amount of data transferred to/from workloads from/to I/Oadapters, and/or the amount of data transferred between the nodes byworkloads operating in other nodes.

At block 406, the hypervisor determines whether or not the mappingsgenerated at block 404 have exceeded a bandwidth threshold. In someembodiments, the bandwidth threshold may be user defined before the dataaccess patterns are monitored at block 402. In certain embodiments, thebandwidth threshold may be determined based upon bandwidth requirementsof the SMP server since the max bandwidth of each cable connectedbetween nodes of the SMP server is known. In certain embodiments, thebandwidth threshold for one data access pattern and mapping may be adifferent bandwidth threshold for a second data access pattern andmapping. For example, a hypervisor may be defined such that thebandwidth threshold for memory reads and writes across two nodes may be2 Gigabytes per second whereas the bandwidth threshold for hardwareaccess (e.g., accelerators, SSD) may be 10 Gigabytes per second. If thedata access patterns do not exceed the bandwidth thresholds, thehypervisor may continue to monitor the data access patterns at block402.

In response to determining that the data access patterns have exceeded abandwidth threshold, the hypervisor may formulate an asymmetric cablingplan (e.g., FIG. 3) for the SMP server at block 408. In someembodiments, formulating an asymmetric cabling plan may includedetermining which nodes within the SMP server are communicating witheach other more frequently. For example, in an SMP server where adatabase is consuming 144 cores (e.g., spanning across three nodes whereeach node contains 48 cores) and a webserver is consuming 48 cores(e.g., spanning across a fourth node), the cabling plan of the SMPserver may be evaluated to determine which cables should be altered inorder to provide more bandwidth between the three nodes while stillmaintaining a minimum bandwidth between the fourth node and the othernodes in the server.

In another example, an SMP server has a database which is consuming 48cores (e.g., spanning across a first node where each node within the SMPserver contains 48 cores) and the SMP server has an applicationutilizing the database, which is also consuming 48 cores (e.g., spanningacross a second node). Further, the SMP server has a similar databaseconsuming 48 cores (e.g., spanning across a third node) with anapplication utilizing the similar database consuming 48 cores (e.g.,spanning across a fourth node). The cabling plan of the SMP server maybe evaluated to determine which cables should be altered to provide morebandwidth between the first and second nodes and the third and fourthnodes since they communicate with each other more frequently.

At block 410, a recommendation to alter the fabric link aggregation ofthe SMP server is displayed to a user through a graphical userinterface. In some embodiments, displaying the recommendation mayinclude the location codes of the cables which need to be altered toconform to the asymmetric plan created at block 408. In certainembodiments, displaying the recommendation may include a pictorialrepresentation of the original system (e.g., FIG. 2) next to a pictorialrepresentation of the recommended system (e.g., FIG. 3). The pictorialrepresentations of the original system and the recommended system may beinteracted with by a user such that, if a user wishes to change theasymmetric cabling plan created at block 408, the user may alter theasymmetric cabling plan and view the projected bandwidth trafficpatterns through the graphical user interface. In embodiments, basedupon the recommended asymmetric cabling plan at the graphical userinterface, indicator lights can be used to visually differentiate cableswithin the single SMP server. For example, the indicator lights forcable identification may illuminate cables to be altered to helpfacilitate altering the physical cables of the SMP server.

The present invention may be a system, a method, and/or a computerprogram product. The computer program product may include a computerreadable storage medium (or media) having computer readable programinstructions thereon for causing a processor to carry out aspects of thepresent invention.

The computer readable storage medium can be a tangible device that canretain and store instructions for use by an instruction executiondevice. The computer readable storage medium may be, for example, but isnot limited to, an electronic storage device, a magnetic storage device,an optical storage device, an electromagnetic storage device, asemiconductor storage device, or any suitable combination of theforegoing. A non-exhaustive list of more specific examples of thecomputer readable storage medium includes the following: a portablecomputer diskette, a hard disk, a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), a static random access memory (SRAM), a portablecompact disc read-only memory (CD-ROM), a digital versatile disk (DVD),a memory stick, a floppy disk, a mechanically encoded device such aspunch-cards or raised structures in a groove having instructionsrecorded thereon, and any suitable combination of the foregoing. Acomputer readable storage medium, as used herein, is not to be construedas being transitory signals per se, such as radio waves or other freelypropagating electromagnetic waves, electromagnetic waves propagatingthrough a waveguide or other transmission media (e.g., light pulsespassing through a fiber-optic cable), or electrical signals transmittedthrough a wire.

Computer readable program instructions described herein can bedownloaded to respective computing/processing devices from a computerreadable storage medium or to an external computer or external storagedevice via a network, for example, the Internet, a local area network, awide area network and/or a wireless network. The network may comprisecopper transmission cables, optical transmission fibers, wirelesstransmission, routers, firewalls, switches, gateway computers and/oredge servers. A network adapter card or network interface in eachcomputing/processing device receives computer readable programinstructions from the network and forwards the computer readable programinstructions for storage in a computer readable storage medium withinthe respective computing/processing device.

Computer readable program instructions for carrying out operations ofthe present invention may be assembler instructions,instruction-set-architecture (ISA) instructions, machine instructions,machine dependent instructions, microcode, firmware instructions,state-setting data, or either source code or object code written in anycombination of one or more programming languages, including an objectoriented programming language such as Smalltalk, C++ or the like, andconventional procedural programming languages, such as the “C”programming language or similar programming languages. The computerreadable program instructions may execute entirely on the user'scomputer, partly on the user's computer, as a stand-alone softwarepackage, partly on the user's computer and partly on a remote computeror entirely on the remote computer or server. In the latter scenario,the remote computer may be connected to the user's computer through anytype of network, including a local area network (LAN) or a wide areanetwork (WAN), or the connection may be made to an external computer(for example, through the Internet using an Internet Service Provider).In some embodiments, electronic circuitry including, for example,programmable logic circuitry, field-programmable gate arrays (FPGA), orprogrammable logic arrays (PLA) may execute the computer readableprogram instructions by utilizing state information of the computerreadable program instructions to personalize the electronic circuitry,in order to perform aspects of the present invention.

Aspects of the present invention are described herein with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to embodiments of theinvention. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer readable program instructions.

These computer readable program instructions may be provided to aprocessor of a general purpose computer, special purpose computer, orother programmable data processing apparatus to produce a machine, suchthat the instructions, which execute via the processor of the computeror other programmable data processing apparatus, create means forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks. These computer readable program instructionsmay also be stored in a computer readable storage medium that can directa computer, a programmable data processing apparatus, and/or otherdevices to function in a particular manner, such that the computerreadable storage medium having instructions stored therein comprises anarticle of manufacture including instructions which implement aspects ofthe function/act specified in the flowchart and/or block diagram blockor blocks.

The computer readable program instructions may also be loaded onto acomputer, other programmable data processing apparatus, or other deviceto cause a series of operational steps to be performed on the computer,other programmable apparatus or other device to produce a computerimplemented process, such that the instructions which execute on thecomputer, other programmable apparatus, or other device implement thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof instructions, which comprises one or more executable instructions forimplementing the specified logical function(s). In some alternativeimplementations, the functions noted in the block may occur out of theorder noted in the figures. For example, two blocks shown in successionmay, in fact, be executed substantially concurrently, or the blocks maysometimes be executed in the reverse order, depending upon thefunctionality involved. It will also be noted that each block of theblock diagrams and/or flowchart illustration, and combinations of blocksin the block diagrams and/or flowchart illustration, can be implementedby special purpose hardware-based systems that perform the specifiedfunctions or acts or carry out combinations of special purpose hardwareand computer instructions.

The descriptions of the various embodiments of the present disclosurehave been presented for purposes of illustration, but are not intendedto be exhaustive or limited to the embodiments disclosed. Manymodifications and variations will be apparent to those of ordinary skillin the art without departing from the scope and spirit of the describedembodiments. The terminology used herein was chosen to explain theprinciples of the embodiments, the practical application or technicalimprovement over technologies found in the marketplace, or to enableothers of ordinary skill in the art to understand the embodimentsdisclosed herein.

What is claimed is:
 1. A system for leveraging multiprocessor fabriclink aggregation, the system comprising: a processor; a computerreadable storage medium having program instructions embodied therewith,the program instructions executable by the processor to cause the systemto perform a method, the method comprising: monitoring, by at least onehypervisor, data access patterns between at least three nodes within asingle symmetric multiprocessing server, wherein the data accesspatterns are associated with the multiprocessor fabric link aggregation;generating, at the least one hypervisor, mappings for the data accesspatterns at the least three nodes, wherein the mappings for the dataaccess patterns comprise at least one of an amount of data transferredbetween workloads across the at least three nodes, an amount of datatransferred between workloads and input and output adaptors, and anamount of data transferred between one of the at least three nodes byworkloads operating in another one of the at least three nodes;determining, based upon the mappings, the data access patterns for atleast two of the at least three nodes are outside of a bandwidththreshold; formulating, in response to determining the data accesspatterns for at least two of the at least three nodes goes outside of abandwidth threshold, an asymmetric cabling plan for the at least threenodes within the single symmetric multiprocessor server; and displayingto a user through a graphical user interface, based upon the asymmetriccabling plan, a recommendation to alter the multiprocessor fabric linkaggregation.
 2. The system of claim 1, wherein the recommendationincludes location codes of cables to be altered and a pictorialrepresentation of changes to be made within the single symmetricmultiprocessing server.
 3. The system of claim 2, wherein the pictorialrepresentation is a graphical user interface.
 4. The system of claim 1,further including visually differentiating cables within the singlesymmetric multiprocessing server based upon the recommendation.
 5. Acomputer program product for leveraging multiprocessor fabric linkaggregation, the computer program product comprising a computer readablestorage medium having program instructions embodied therewith, whereinthe computer readable storage medium is not a transitory signal per se,the program instructions executable by a computer to cause the computerto perform a method, the method comprising: monitoring, by at least onehypervisor, data access patterns between at least three nodes within asingle symmetric multiprocessing server, wherein the data accesspatterns are associated with the multiprocessor fabric link aggregation;generating, at the least one hypervisor, mappings for the data accesspatterns at the least three nodes, wherein the mappings for the dataaccess patterns include at least one of an amount of data transferredbetween workloads across the at least three nodes, an amount of datatransferred between workloads and input and output adaptors, and anamount of data transferred between one of the at least three nodes byworkloads operating in another one of the at least three nodes;determining, based upon the mappings, the data access patterns for atleast two of the at least three nodes are outside of a bandwidththreshold; formulating, in response to determining the data accesspatterns for at least two of the at least three nodes goes outside of abandwidth threshold, an asymmetric cabling plan for the at least threenodes within the single symmetric multiprocessor server; and displayingto a user through a graphical user interface, based upon the asymmetriccabling plan, a recommendation to alter the multiprocessor fabric linkaggregation.
 6. The computer program product of claim 5, wherein therecommendation includes location codes of cables to be altered and apictorial representation of changes to be made within the singlesymmetric multiprocessing server.
 7. The computer program product ofclaim 6, wherein the pictorial representation is a graphical userinterface.
 8. The computer program product of claim 5, further includingvisually differentiating cables within the single symmetricmultiprocessing server based upon the recommendation.